An aqueous pink solution of cobalt(II) chloride changes to deep blue on addition of excess of HCl. This is because ........

a. CoH2O62+ is transformed into CoCl64-

b. CoH2O62+ is transformed intCoCl42-


c. Tetrahedral complexes have smaller crystal field splitting than octahedral complexes

d. Tetrahedral complexes have larger crystal field splitting than octahedral complex 

Choose the correct option
1. (a, b)
2. (b, c)
3. (c, d)
4. (a, c)

Aqueous pink solution of cobalt (II) chloride is due to the electronic transition of electron fom t2g to eg, the energy level of CoH2O62+ complex. When an excess of HCI is added to this solution

(i) CoH2O62+ is transformed into CoCl42-

(ii) Tetrahedral complexes have smaller crystal field splitting than octahedral complexes because t=49 0

Hence, options (b) and (c) are correct choices.